/*********************************************************************************
This code is provided for internal research and development purposes by Huawei solely,
in accordance with the terms and conditions of the research collaboration agreement of May 7, 2020.
Any further use for commercial purposes is subject to a written agreement.
 *  OKVIS - Open Keyframe-based Visual-Inertial SLAM
 *  Copyright (c) 2015, Autonomous Systems Lab / ETH Zurich
 *  Copyright (c) 2016, ETH Zurich, Wyss Zurich, Zurich Eye
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 * 
 *   * Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright notice,
 *     this list of conditions and the following disclaimer in the documentation
 *     and/or other materials provided with the distribution.
 *   * Neither the name of Autonomous Systems Lab / ETH Zurich nor the names of
 *     its contributors may be used to endorse or promote products derived from
 *     this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 *
 *  Created on: Aug 30, 2013
 *      Author: Stefan Leutenegger (s.leutenegger@imperial.ac.uk)
 *    Modified: Zurich Eye
 *********************************************************************************/

/**
 * @file PoseLocalParameterization.hpp
 * @brief Header file for the PoseLocalParemerization class.
 * @author Stefan Leutenegger
 */

#pragma once

#pragma diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
// Eigen 3.2.7 uses std::binder1st and std::binder2nd which are deprecated since c++11
// Fix is in 3.3 devel (http://eigen.tuxfamily.org/bz/show_bug.cgi?id=872).
#include <ceres/ceres.h>
#pragma diagnostic pop

#include <ze/nlls/local_parameterization_additional_interfaces.hpp>

namespace ze {
namespace nlls {

/// \brief Pose local parameterisation, i.e. for orientation dq(dalpha) x q_bar.
/// Order:
/// x[0]-x[2] translation
/// x[3]-x[6] quaternion xyzw
/// Perturbation:
/// dx[0] - dx[2] translation
/// dx[3] - dx[5] axis angle perturbation
class PoseLocalParameterization :
    public ceres::LocalParameterization,
    public LocalParamizationAdditionalInterfaces
{
 public:

  /// \brief Trivial destructor.
  virtual ~PoseLocalParameterization() = default;

  /// \brief Generalization of the addition operation,
  ///        x_plus_delta = Plus(x, delta)
  ///        with the condition that Plus(x, 0) = x.
  /// @param[in] x Variable.
  /// @param[in] delta Perturbation.
  /// @param[out] x_plus_delta Perturbed x.
  virtual bool Plus(const double* x, const double* delta,
                    double* x_plus_delta) const;

  /// \brief Computes the minimal difference between a variable x and a perturbed variable x_plus_delta.
  /// @param[in] x Variable.
  /// @param[in] x_plus_delta Perturbed variable.
  /// @param[out] delta minimal difference.
  /// \return True on success.
  virtual bool Minus(const double* x, const double* x_plus_delta,
                     double* delta) const;

  /// \brief The jacobian of Plus(x, delta) w.r.t delta at delta = 0.
  /// @param[in] x Variable.
  /// @param[out] jacobian The Jacobian.
  virtual bool ComputeJacobian(const double* x, double* jacobian) const;

  /// \brief Computes the Jacobian from minimal space to naively overparameterised
  /// space as used by ceres. It is the inverse of the plusJacobian.
  /// @param[in] x Variable.
  /// @param[out] jacobian the Jacobian (dimension minDim x dim).
  /// \return True on success.
  virtual bool ComputeLiftJacobian(const double* x, double* jacobian) const;

  // provide these as static for easy use elsewhere:

  /// \brief Generalization of the addition operation,
  ///        x_plus_delta = Plus(x, delta)
  ///        with the condition that Plus(x, 0) = x.
  /// @param[in] x Variable.
  /// @param[in] delta Perturbation.
  /// @param[out] x_plus_delta Perturbed x.
  static bool plus(const double* x, const double* delta, double* x_plus_delta);

  /// \brief The jacobian of Plus(x, delta) w.r.t delta at delta = 0.
  /// @param[in] x Variable.
  /// @param[out] jacobian The Jacobian.
  static bool plusJacobian(const double* x, double* jacobian);

  /// \brief Computes the minimal difference between a variable x and a perturbed variable x_plus_delta
  /// @param[in] x Variable.
  /// @param[in] x_plus_delta Perturbed variable.
  /// @param[out] delta minimal difference.
  /// \return True on success.
  static bool minus(const double* x, const double* x_plus_delta, double* delta);

  /// \brief Computes the Jacobian from minimal space to naively overparameterised space as used by ceres.
  /// @param[in] x Variable.
  /// @param[out] jacobian the Jacobian (dimension minDim x dim).
  /// \return True on success.
  static bool liftJacobian(const double* x, double* jacobian);

  /// \brief The parameter block dimension.
  virtual int GlobalSize() const
  {
    return 7;
  }

  /// \brief The parameter block local dimension.
  virtual int LocalSize() const
  {
    return 6;
  }

  // added convenient check
  bool VerifyJacobianNumDiff(const double* x, double* jacobian,
                             double* jacobianNumDiff);
};

}  // namespace nlls
}  // namespace ze
